1. Field of Utilization in Industry
The present invention relates to rolling mill facilities having strip shape detection equipment, and in particular to, a rolling mill facility that has strip shape detection equipment having strip shape detecting devices installed at least on one of the inlet side and the outlet side of the rolling mill that rolls metal strips, permitting the measurement of the strip shape using such shape detected equipment, having a high productivity, and being ideally suitable for obtaining strips with excellent strip shape.
2. Prior Art
Conventionally, as has been described in pages 269-270 of xe2x80x9cTheory and Practice of Rollingxe2x80x9d published by The Iron and Steel Institute of Japan, the most widely used type is the segmented roller type in which shape detecting devices are installed in the shape detection equipment for measuring the strip shape after rolling the metal strip s, and the body part of the detection roller is segmented with a pitch of about 50 mm, the weight load on each of those rings is measured, and from them, the tension distribution is calculated, and from that tension distribution conversion is made to the strip shape of the strip thereby measuring strip shape of the strip. The accuracy in such segmented roller types will be high because they allow measurement of the direct tension distribution for each segment ring.
However, the following problems are present in said conventional technologies.
That is, since the strip shape detecting device of the conventional segmented roller type divides the body part of the rotating sensor roller into several segments and has a complicated construction in which different load cells are incorporated for each segment, although the detection accuracy is good, the device becomes extremely expensive. In addition, because of being of the segmented roller type, there is the fear of scratching the surface of the strip in each segment and of bad effects of thermal deformation due to heat transfer from the strip.
An object of the present invention is to provide a rolling mill facility having a strip shape detection equipment with a simple construction, and using which it is possible to measure easily the strip shape of the metal strip after rolling.
The rolling mill facility having strip shape detection equipment according to the present invention adopts the following construction in order to achieve the above object.
(1) Firstly, in the present invention, the rolling mill facility comprises at least one rolling mill having a pair of top and bottom work rolls that roll the strips, and a strip shape detection equipment in which a shape detecting device is installed at least on one of the inlet and outlet sides of the rolling mill, and the strip shape detecting device comprises one roller on which the metal strip is wound, at least two bearing boxes on one side and four bearing boxes on both sides provided on an operating side end section and a driving side end section, respectively, of that roller, and supporting the roller in a free-to-rotate manner, and at least two load cells on one side or four load cells on both sides, with the load cells being provided on the bearing boxes, respectively, and capable of measuring the supporting load on each of the bearing boxes.
By constructing such a strip shape detecting device with one roller, two bearing boxes on one side or four bearing boxes on both sides, and two load cells on one side or four load cells on both sides, the tension distribution of the strip can be calculated from the load values measured by the load cells, that tension distribution can be converted into the strip shape of the strip, thus indirectly measuring the strip shape of the strip, and hence it becomes possible to measure easily the strip shape of the metal strip after rolling with a simple construction.
In addition, since the roller is a non-segmented integrated construction roller, there is no problem of causing scratches on the surface of the strip, and also there are no bad effects of thermal deformation due to heat transfer from the strip, and hence the durability gets improved.
(2) In (1) above, preferably, the strip shape detection equipment is additionally provided with a means for calculating the tension distribution of the strip from the load values measured by the load cells of the strip shape detecting device, and for converting that tension distribution into the strip shape of the strip
Because of this, it is possible to carry out automatically and instantaneously the calculation of the strip shape after measuring the load values.
(3) Further, in (2) above, preferably, the means for calculating the strip shape of the strip converts to the strip shape of the operation side half of the strip from the load measured by the two load cells provided in the bearing boxes on the operation side end section of the strip shape detector, and converts to the strip shape of the driving side half of the strip from the load measured by the two load cells provided in the bearing boxes on the driving side end section of the strip shape detector.
Because of this, it is possible to calculate the entire strip shape.
(4) Further, in (1) above, preferably, the strip shape detecting devices respectively on the two bearing boxes on each side are provided additionally with a means on any one bearing box out of the two bearing boxes on each side for applying pre-load on the bearing box in the direction of the supporting load.
Because of this, since it becomes possible to kill the gap between the bearing box and the load cell, it will be possible to measure the load using load cells with a good accuracy.
(5) In (1) above, preferably, said shape detection equipment is additionally provided with an edge position detecting device that detects the amount of meandering movement of the strip, and a means that not only calculates the operating side plate width range and the driving side plate width range according to the detected value from that edge position detecting device, but also converts to the strip shape of the plate width range of the strip on the operation side from the load measured by the two load cells provided on the bearing boxes in the operation side end section of said shape detecting device, and converts to the strip shape of the plate width range of the strip on the driving side from the load measured by the two load cells provided on the bearing boxes in the driving side end section of said shape detecting device.
Because of this, even when there is meandering movement of the plate, it will be possible to detect the shape by compensating for that meandering movement.
(6) In (1) above, preferably, the strip shape detection equipment is additionally provided with a displacement measurement means that measures the roller surface displacement in the tension supporting direction at at least one location of the roller of the strip shape detecting device, and a means for calculating the tension distribution of the strip from the load measured by the load cells of the strip shape detecting device and the values measured by the displacement measurement means, and converts that tension distribution into the strip shape of the strip.
Because of this, it will be possible to detect shapes of compound buckle in addition to center buckle and edge buckle shapes.
(7) In (1) above, preferably, the rolling mill facility is provided with a control means that carries out feedback control of the strip shape controlling means of the rolling mill so that the difference between the shape measured by the strip shape detecting device on the outlet side of the rolling mill equipment and the previously set target strip shape becomes small.
Because of this, it will be possible to increase the acceleration rate at the time of starting the rolling operation, and also to increase the production efficiency because the frequency of strip exhaustion gets decreased.
(8) Further, in the present invention, the rolling mill facility comprises at least one rolling mill having a pair of top and bottom work rolls that roll the strips, and a strip shape detection equipment in which a shape detecting device is installed at least on one of the inlet and outlet sides of the rolling mill, the strip shape detecting device comprises one roller on which the metal strip is wound, and at least two bearing boxes on one side and four bearing boxes on both sides provided on an operating side end section and the driving side end section, respectively, of that roller, and supporting the roller in a free-to-rotate manner, and the strip shape detection equipment measures the supporting load on the bearing boxes of the strip shape detecting devices and the supporting moment, calculates the tension distribution of the strip from these measured values, and converts that tension distribution into the strip shape of the strip.
Because of this, it will be possible to calculate the tension distribution of the strip, to convert that tension distribution into the strip shape of the strip, thus indirectly measuring the strip shape of the strip, and hence to measure easily the strip shape of the metal strip after rolling with a simple construction.
In addition, since the roller is a non-segmented integrated construction roller, there is no problem of causing scratches on the surface of the strip, and also there are no bad effects of thermal deformation due to heat transfer from the strip, and hence the durability gets improved.
(9) Further, in the present invention, the rolling mill facility comprises at least one rolling mill having a pair of top and bottom work rolls that roll the strips, and a strip shape detection equipment in which a strip shape detecting device is installed at least on one of the inlet and outlet sides of the rolling mill, the strip shape detecting device comprises one roller on which the metal strip is wound, and at least one bearing box on one side and two bearing boxes on both sides, provided on the operating side end section and the driving side end section, respectively, of that roller, and supporting the roller in a free-to-rotate manner, and the strip shape detection equipment approximates the tension distribution of the strip using a function in the plate width direction and having several unknown coefficients, and measures the same number of parameters as the number of unknown coefficients among the parameters of the supporting load on the bearing boxes, the supporting moment on the bearing boxes, the deflection of the roller, the deflection angle of the roller, and/or the roller bending stress, and prepares condition equations equal in number to the number of the unknown coefficients from these measured values, computes the unknown coefficients and calculates the strip tension distribution, and converts that tension distribution into the strip shape of the strip.
Because of this, it will be possible to calculate the tension distribution of the strip, to convert that tension distribution into the strip shape of the strip, thus indirectly measuring the strip shape of the strip, and hence to measure easily the strip shape of the metal strip after rolling with a simple construction.
In addition, since the roller is a non-segmented integrated construction roller, there is no problem of causing scratches on the surface of the strip, and also there are no bad effects of thermal deformation due to heat transfer from the strip, and hence the durability gets improved.